Leviathans are docile sea creatures who dwell in the oceans of the Dragon Realms, only appearing in first two chapters of The Legend of Spyro series. They resemble giant sea turtles with three pairs of flippers.
The same Leviathan appeared again, saving Spyro from possible drowning when he entered a dream in mid-flight after defeating Skabb. It brought him to the White Isle where The Chronicler lives. Once there, the Leviathan was thanked by Sparx as it swam off back to sea. The Leviathan was possibly sent by the Chronicler to take Spyro to the Isle after the Chronicler summons Spyro again.